ADB Wi-Fi debugging fails with "No route to host" despite ADB enabled on device: verify network path and macOS firewall settings

Android

If you're unable to connect to your Esper-managed Android device via ADB over Wi-Fi and receive a No route to host error, this article will help you diagnose and resolve the issue. This error typically indicates a network or firewall problem on your host machine rather than an issue with the device itself.

Before you begin

Make sure that:

You have confirmed the device's current IP address in the Esper Console
Internet ADB Switcher is enabled on the device at Devices & Groups → [Device Name] → Settings → Connected devices
You can ping the device from your host machine (this confirms basic network connectivity)
You are using the correct IP address and port in your ADB command: ./adb connect 192.168.1.114:5555

Step 1: Verify the device's current IP address

DHCP leases expire and IP addresses change. Do not rely on a previously noted address.

In the Esper Console, go to Devices & Groups → [Device Name] → Device Info
Note the IP address shown for your device
Use this IP address when attempting to connect via ADB

Step 2: Confirm ADB is enabled on the device

In the Esper Console, navigate to Devices & Groups → [Device Name] → Settings → Connected devices
Verify that Internet ADB Switcher is toggled ON
If you recently applied this setting via a Blueprint, wait for the Blueprint to converge on the device and retry

Step 3: Test TCP connectivity to port 5555

Run the following command from your host machine to test if port 5555 is reachable:

nc -zv 192.168.1.114 5555

If this command times out or returns No route to host while ping succeeds, the issue is firewall or routing based, not an ADB daemon issue. Continue to the next steps.

Step 4: Check your macOS firewall settings

If you are on macOS, firewall or network filter settings may be blocking your ADB connection.

On your Mac, go to System Settings → Network → Firewall (macOS Ventura and later) or System Preferences → Security & Privacy → Firewall (older versions)
Ensure that outbound connections are not blocked for Terminal or the adb process
If your Mac is managed by your organization, contact your IT department to check for any MDM-enforced firewall or packet filter rules that may be blocking port 5555

Step 5: Check for VPN interference

If a VPN is active on your host machine, it may be routing traffic for your local subnet (192.168.x.x) through the tunnel or dropping traffic to local addresses.

Temporarily disable any active VPN on your host machine
Retry the ADB connection:
```
./adb connect 192.168.1.114:5555
```
If the connection succeeds, work with your IT department to configure your VPN to allow local network access

Step 6: Verify you are on the same network segment

Confirm that your host machine and Android device are on the same network and that client isolation is not enabled.

Verify that your Mac and Android device are connected to the same VLAN
If you are using Wi-Fi, check your wireless network settings to ensure that client isolation (also called AP isolation) is not enabled, as this blocks device-to-device traffic even on the same SSID

Step 7: Reboot your host machine

Transient network stack issues can sometimes cause port-level blocks that clear after a restart.

Reboot your Mac
Retry the ADB connection:
```
./adb connect 192.168.1.114:5555
```

Step 8: Verify the connection

A successful connection returns:

connected to 192.168.1.114:5555

Confirm that your device appears in the output of ./adb devices with a status of device (not offline or unauthorized).

Still need help?

If you have completed all steps above and the issue persists, contact Esper Support. provide the following information:

The output of nc -zv 192.168.1.114 5555 from your host machine
The output of ping 192.168.1.114 from your host machine
The exact error message you receive when running ./adb connect 192.168.1.114:5555
Your host machine's operating system and version (for example, macOS 14.2)
Whether ADB over Wi-Fi was previously working and what may have changed since then